5
SAI Series
Features
●Surface-mount package with high output and
efficiency
●Requires only 4 external components
●Phase correction and output voltage adjustment
performed internally
●Built-in reference oscillator (60 kHz)
●Built-in overcurrent and thermal protection circuits
Applications
●For power supplies in telephone sets
●For power supplies in office equipment External View
Type No. VO (V) IO (A)
SAI01 5
SAI02 3.3
SAI03 12
SAI04 15 0.4
SAI05 13
SAI06 9
■Absolute Maximum Ratings
Parameter Symbol Ratings Unit
DC Input Voltage VIN 35 V
Power Dissipation PD0.75 W
Junction Temperature Tj+125 °C
Storage Temperature Tstg –40 to +125 °C
SW Terminal Applied Reverse Voltage VSW –1 V
Thermal Resistance* (junction-to-case) Rth(j-c) 20 °C/W
* Refer to Outline Drawing for the case temperature measuring points.
■Recommended Operating Conditions
0.5
■Lineup
Switching Type Surface-mount and Separate Excitation Type
Ratings
Parameter Symbol SAI01 SAI02 SAI03 SAI04 SAI05 SAI06 Unit
DC Input Voltage Range VIN
7 to 33 5.3 to 33 15 to 33 18 to 33 16 to 33 12 to 33
V
Output Current Range IO 0 to 0.5 0 to 0.4 A
Operating Junction Temperature Range Tjop –30 to +125 °C
6
Ratings
Parameter Symbol SAI01 SAI02 SAI03 SAI04 SAI05 SAI06 Unit
min typ max min typ max min typ max min typ max min typ max min typ max
VO
4.80 5.00 5.20 3.17 3.30 3.43 11.40 12.00 12.60 14.25 15.00 15.75 12.35 13.00 13.65 8.55 9.00 9.45
Condition
V
IN
=20V, I
O
=0.3A V
IN
=15V, I
O
=0.3A V
IN
=24V, I
O
=0.3A V
IN
=27V, I
O
=0.3A V
IN
=25V, I
O
=0.3A V
IN
=21V, I
O
=0.3A
η
80 75 88 89 88 86
Condition
VIN=20V, IO=0.3A V
IN
=15V, I
O
=0.3A V
IN
=24V, I
O
=0.3A V
IN
=27V, I
O
=0.3A V
IN
=25V, I
O
=0.3A V
IN
=21V, I
O
=0.3A
f
60 60 60 60 60 60
Condition
V
IN
=20V, I
O
=0.3A V
IN
=15V, I
O
=0.3A V
IN
=24V, I
O
=0.3A V
IN
=27V, I
O
=0.3A V
IN
=25V, I
O
=0.3A V
IN
=21V, I
O
=0.3A
∆VOLINE
80 100 60 80 100 130 100 130 100 130 90 110
Condition
V
IN
=10 to 30V, I
O
=0.3A V
IN
=8 to 30V, I
O
=0.3A V
IN
=18 to 30V, I
O
=0.3A V
IN
=21 to 30V, I
O
=0.3A V
IN
=19 to 30V, I
O
=0.3A V
IN
=15 to 30V, I
O
=0.3A
∆VOLOAD
30 40 20 30 70 95 90 120 75 100 50 80
Condition
V
IN
=20V, I
O
=0.1 to 0.4A V
IN
=15V, I
O
=0.1 to 0.4A V
IN
=24V, I
O
=0.1 to 0.4A V
IN
=27V, I
O
=0.1 to 0.4A V
IN
=25V, I
O
=0.1 to 0.4A V
IN
=21V, I
O
=0.1 to 0.4A
Temperature Coefficient ∆Vo/∆T
±0.5 ±0.5 ±1.5 ±1.5 ±1.5 ±1.0
of Output Voltage
RREJ
45 45 45 45 45 45
Condition
f=100 to 120Hz
IS
0.55 0.55 0.45 0.45 0.45 0.45
Condition
VIN=10V VIN=8V VIN=18V VIN=21V VIN=19V VIN=15V
■Electrical Characteristics
■Outline Drawing (unit:mm) ■Block Diagram
a. Type
b. Lot number
A Case temperature
measuring point
Plastic Mold Package Type
Flammability: UL94V-0
Weight: Approx. 0.22 g
SAI Series
Output Voltage V
Efficiency %
Switching Frequency kHz
Line Regulation mV
Load Regulation mV
mV/°C
Ripple Rejection dB
Overcurrent Protection A
Starting Current
Terminal Connections
(1)Input
(2)Switching output
(3)Output Voltage
Detection
(4)Ground
A
3V
OS
ab
4
.GND
2 SW
1V
IN
6.8
max.
4.0
max.
4.7
max.
2.54
±0.25
4.32
±0.2
8.0
±0.5
3.6
±0.2
1.4
±0.2
3.0
±0.2
9.8
±0.3
0~0.1
6.3
±0.2
1.0
±0.3
0.89
±0.15
0.26 0.75
+0.15
–0.05
0.3
+0.15
–0.05
SW
VOS
VIN
4
GND
3
21
Osc
Reg.
Ocp
Comp.
Reset
Drive
TSD
Amp.
VREF
7
■Example of Printed-circuit board
The efficiency depends on the input voltage and the
output current. Thus, obtain the value from the
efficiency graph on page 8 and substitute the per-
centage in the formula above.
VO: Output voltage
IO: Output current
ηχ
: Efficiency (%)
VF: Diode forward voltage
SFPB54-0.3V
Thermal design for D1 must be performed sepa-
rately.
■Selecting external components
1. Inductor L1
q It must be suited for switching regulators.
Do not use inductors for noise filters as they generate excessive heat.
w It must have the appropriate inductance value.
If the inductance is too small (150
µ
H or lower), abnormal oscillation may occur causing operation problems in
the overcurrent protection circuit within the rated current range.
e The rated current must be satisfied.
If the rated current is exceeded, magnetic saturation leads to overcurrent.
2. Capacitors C1 and C2
q They must satisfy the breakdown voltage and allowable ripple current.
Use of these capacitors over their derating values shortens their service lives and may also cause abnormal
oscillation of the IC.
w C2 must be a low-impedance type capacitor.
A low-impedance type capacitor is recommended for C2 to ensure minimum ripple voltage and stable switching
operation.
3. Diode D1
The Sanken SFPB54 diode is recommended for D1. If you intend to use an equivalent diode, be sure to make use
of a Schottky barrier diode and make sure that the reverse voltage applied to terminal 2 of the IC does not exceed
the value (–1V) given in the absolute maximum ratings. If you use a fast recovery diode or any other diode, application
of a reverse voltage generated from the recovery or ON voltage of the diode may damage the IC.
a) For optimum operation,
there must be only one
GND line originating from
terminal 4 and each com-
ponent must be con-
nected with the shortest
possible wiring.
b) To prevent heating of the
IC, it is best to make the
GND pattern larger since
the internal frame and ter-
minal 4 (GND) are con-
nected to each other.
■Standard External Circuit ■Ta-PD Characteristics
+
+
VIN
DI1 C1L1
C
2GND
SW
Vo
12
34
SAI
V
IN
C1 D1
L1
3.3V
5V
: 200µH
12V
13V
15V
: 300µH
100µFC2
330µF
VIN
DC Input
VOUT
DC Output
SFPB54
(Sanken)
GND
GND GND
SAI
SW
VOS
12
3
4
+ +
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
-30 0 25 50 75 100 125
• Glass epoxy substrate
(95 × 69 × 1.2)
• Natural cooling
Power Dissipation P
D
(W)
Ambient temperature Ta (°C)
–VF • IOVO
1– VIN
PD = VO • IO100 –1
ηχ
8
SAI Series Typical Characteristics
SAI Series
Rise Characteristics Efficiency Characteristics Load Regulation
(SAI01) (SAI01) (SAI01)
0
6
5
4
3
2
1
50 100
Case Temperature T
C
(°C)
150 200
V
IN
=20V,I
O
=20mA
Output Voltage V
O
(V)
0
14
12
10
8
6
4
2
510
Input Voltage VIN (V) 15 20
Ta=25°C
IO
0A
0.2A
0.4A
Output Voltage VO (V)
0
100
90
80
70
60
50
40
0.1 0.2
Output Current I
O
(A)0.3 0.4
Ta=25°C
V
IN
15V
24V
33V
Efficiency η
(%)
0
12.3
12.2
12.1
12.0
11.9
11.8
0.1 0.2
Output Current I
O
(A)0.3 0.4
Output Voltage V
O
(V)
Ta=25°C
V
IN
33V 24V
20V
15V
Temperature Characteristics Overcurrent Protection Thermal Protection
(SAI01) Characteristics (SAI01) Characteristics (SAI01)
Rise Characteristics Efficiency Load Regulation
(SAI03) Characteristics (SAI03) (SAI03)
6
5
4
3
2
1
00246
Input Voltage V
IN
(V)
I
OUT
0.1A
0.5A
Output Voltage V
O
(V)
810
0A
Ta=25°C
100
90
80
70
60
50
40
Efficiency η
(%)
0 0.1 0.2 0.3
Output Current I
O
(A) 0.4 0.5
Ta=25°C
V
IN
7V
20V
33V
10V
25V
5.3
5.2
5.1
5.0
4.9
4.8
4.7
V
IN
33V
20V
10V
7V
Output Voltage V
O
(V)
0 0.1 0.2 0.3
Output Current I
O
(A)
0.4 0.5
Ta=25°C
100
90
80
70
60
50
40
0
Efficiency η
(%) frequency f (kHz)
Outoput Voltage Vo (V)
–50 0 50
Ambient Temperature Ta (°C)
100 150
V
IN
=20V, I
O
=0.3A
V
O
f
5.3
5.2
5.1
5.0
4.9
4.8
4.7
0
η
Output Voltage V
O
(V)
6
5
4
3
2
1
0 0.5 1.0
Output Current I
O
(A) 1.5 2.0
Ta=25°C
V
IN
20V
33V
7V
